ZF 4spd query

[Sheepdip]

Anyone know how the lockup works - is it electrical or fully hydraulically controlled ?

I ask as having recently fitted ZFand quite like it, one downside is with accelerating reasonably briskly or up hills it changes 3rd -> 4th around 60 and then immediately into lockup, a combined big rev drop which I find disconcerting, especially when towing.It would be better if lockup was on 3rd as well or I could control when it came in.

Ideas?

[Kevin Garrod]

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The only electrical connection on mine is for the reverse lights and inhibitor switch, so I would say it's hydraulic. I think we need Russ to explain exactly how it works.

[Bob Heritage]

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If you experiment with the kickdown cable, you get variable results.I adjusted mine many times before I was happy.

[jbuckl]

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I concur with Rob, went for a drive with a 1/2" spanner ....made a couple of adjustments ....much better.

The upchange is still a bit brisk almost passing through the shifts on part throttle as it were.

The only way to fix this imo. is to design a snail-cam to regulate the kickdown pressure slightly more.

Has anyone done this, using a snail cam or similar?

Btw, the lockup is hydraulically controlled pressure and therefor speed related.

[Sheepdip]

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jbuckl wrote:

I concur with Rob, went for a drive with a 1/2" spanner ....made a couple of adjustments ....much better.

The upchange is still a bit brisk almost passing through the shifts on part throttle as it were.

The only way to fix this imo. is to design a snail-cam to regulate the kickdown pressure slightly more.

Has anyone done this, using a snail cam or similar?

Btw, the lockup is hydraulically controlled pressure and therefor speed related.

Thanks for reply and you too Bob. I know we spoke about this a few times and I have played with it, its just this one annoyance. Most of the time its in top around 35-40 and lockup not a problem, but accelerate briskly or up hills (Not that Suffolk has much of either) and its the big drop in revs at 60 that kicks in, anddown on power.I didsetthe kickdown like yours Bobbut found foot to floor it changed up at 4500, a bit low for me.

I wondered if it was electrical as first time I tried it without connections, lockup didn't work, but must have been adjustment.

I'll continue playing.....

Cheers

Paul

[Bob Heritage]

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Sounds like the kickdown wants shortening a little,

Bob

[Sheepdip]

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Hi Bob, well its setup now with just a little slack at full throttle. I also changed the accelerator arm as old one was bent and not aligning. It is a lot better than the old 65 but just find it irritating when it happens to have what is like going from 3rd to 5th in my Mondy. The changes are smooth, I asked my lad how many gears he could"hear" from standstill to 60, answer was2!

Paul